Python - Types and Operations(file, read, write, open(built-in function), with/as statement)

Learning Python
(Oreilly & Associates Inc)
Mark Lutz (著)
(邦訳版)

開発環境

• OS X Mavericks - Apple(OS)
• Emacs (CUI)、BBEdit - Bare Bones Software, Inc. (GUI) (Text Editor)
• Python 3.4 (プログラミング言語)

Learning Python (Mark Lutz (著)、Oreilly & Associates Inc)のPART Ⅱ.(Types and Operations)、Test Your Knowledge: Part II Exercises 11.(Files)を解いてみる。

その他参考書籍

• Pythonチュートリアル 第2版
• Python クックブック 第2版 (原書(最新版))
• Programming Python
• Python Pocket Reference (Pocket Reference (O'Reilly))

11.(Files)

コード(BBEdit)

sample11_1.py

#!/usr/bin/env python3
#-*- coding: utf-8 -*-

import sys

with open(sys.argv[1], 'w') as f:
    print('Hello file world!', file=f)

sample11_2.py

#!/usr/bin/env python3
#-*- coding: utf-8 -*-

import sys

with open(sys.argv[1]) as f:
    print(f.read(), end='')

入出力結果(Terminal, IPython)

$ ./sample11_1.py myfile.txt
$ ./sample11_2.py myfile.txt
Hello file world!
$ ls myfile.txt 
myfile.txt
$ rm myfile.txt 
remove myfile.txt? y
$ ./sample11_1.py ../myfile.txt
$ ./sample11_2.py ../myfile.txt
Hello file world!
$ ls myfile.txt
ls: myfile.txt: No such file or directory
$ ls ../myfile.txt 
../myfile.txt
$ rm ../myfile.txt 
remove ../myfile.txt? y
$ ./sample11_1.py temp_dir/myfile.txt
Traceback (most recent call last):
  File "./sample11_1.py", line 6, in <module>
    with open(sys.argv[1], 'w') as f:
FileNotFoundError: [Errno 2] No such file or directory: 'temp_dir/myfile.txt'
$ mkdir temp_dir
$ ./sample11_1.py temp_dir/myfile.txt
$ ./sample11_2.py temp_dir/myfile.txt
Hello file world!
$ ls myfile.txt
ls: myfile.txt: No such file or directory
$ ls temp_dir/*
temp_dir/myfile.txt
$